Question

So I am writing a game in Java, and I started out using the drawRect() method to represent players, enemies, and shots. Everything was great.
Then I decided to try to get fancy.
I found myself creating .png images of each object and used the Graphics2D drawImage() method. Everything began to slow down. Is there any alternative way to speed up the process?

My animation is based on a Swing Timer

    public void paint(Graphics g){
    super.paint(g);
    Graphics2D g2d = (Graphics2D)g;
    player1.paintShips(g);
    g2d.drawImage(bGround, 14, 14, this);
    try{
        for(Shot s: liveRounds){ //liveRounds is an ArrayList of Shots
            if(!inBounds.contains(s.getRect()) || villains.collision(s)){
                if(villains.collision(s)){
                    villains.collided(s, this);
                }
                liveRounds.remove(s);
                roundCount--;
            }
            else{
                s.paintShot(g, this);                   
            }
        }
    }catch(ConcurrentModificationException e){};
    villains.paintEnemyGrid(g, this);
    g2d.setColor(Color.cyan);
    g2d.draw(hitZone1);
    g2d.setColor(Color.red);
    g.drawString("X: " + player1.getX(1) + "  Y: " + player1.getY(1), 370, 150);
    g2d.draw(inBounds);
    g.drawString(score + "", 440, 40);
    g.dispose();
} 

Any tips or tutorials on animation?
Thanks

Answer 1

A 10 ms delay is 100 frames per second. That is almost certainly too fast.

Also, if you want to remove an object from a Collection while you are iterating over it, you need to do this:

Iterator<T> itr = collection.iterator();
while(itr.hasNext()) {
    T obj = itr.next();
    if(removeObj) {
        itr.remove();
    }
}

ConcurrentModificationExceptions lead to non-deterministic behavior. You need to avoid them, not ignore them.